FIELD OF THE INVENTION
This invention relates to an adaptor plate having a central opening therethrough and positionable over the central area of the center low step plate of a vehicle rear step bumper with the opening of the adaptor plate registered with the hitch ball mounting opening in the step plate, the threaded shank of a hitch ball being secured downwardly through the openings in the adaptor and step plates.
The adaptor plate includes a forward margin which at least closely opposes the center face plate portion of the step bumper defining the forward extremity of the step plate and opposite side rear portions of the adaptor plate project rearwardly of the rear margin of the step plate and have safety chain hook engagable openings formed therethrough.
By providing the adaptor plate with a forward margin which at least closely opposes the center face plate portion of the associated step bumper, only a single fastener (comprising the threaded shank of the hitch ball) is required to secure the adaptor plate to the step plate in a manner preventing angular displacement of the adaptor plate relative to the step plate.